Antonyms are words that have opposite meanings to a given word. For "declared invalid", the antonyms could include "validated", "approved", "legitimized", "supported", "sanctioned", "authorized", "affirmed", "ratified", "accepted" and "acknowledged". These words indicate that the subject has been verified, deemed acceptable or legally binding. Additionally, words like "confirmed" and "verified" indicate that the initial status was checked and that it is now deemed to be valid. These antonyms are useful to describe situations where something that was previously deemed to be invalid or nullified can be reinstated or supported.